Those of us who were occasionally bullied in grade school (for me it was during my younger years, much less so in my older ones, and even then I didn't get bullied a whole lot, but it did happen) might remember scenarios in which the bigger kid is picking on the smaller, and doing stuff like cornering him someplace alone, and refusing to let him pass, and maybe punching him a bit in the stomach or shoulder. Maybe it gets worse, like dumping the kid's books while he's in the bathroom. Whatever it is -- it's the canonical style of bullying, what people my age tend to think of when they hear the word.
Remember what the bully always said on those rare occasions when a teacher or other adult just happened to show up, coming 'round the corner at just the right time? "I was just kidding around with him!"
"I was just playin'!"
"I wasn't gonna hurt him or anything, we were just playin'!"
"I was just joking with him!"
That's what I think of whenever some comedian says something really awful, gets called on it, and then starts in with the "I was just telling a joke!" defense.
I think that an uncomfortably large amount of comedy these days springs from the same mental space from which bullying comes. And that, no matter what the comedians might wish, is their problem, not mine.